Underwater robot retracting and releasing device and retracting and releasing wave compensation method

Abstract

The invention relates to an underwater robot take-up and pay-off device and a take-up and pay-off wave compensation method. The device comprises a cable storage winch, a wave compensation component, an A frame, a swing stopper, load equipment, an umbilical cable and a controller, and the umbilical cable is connected with the cable storage winch and the load equipment. The wave compensation component comprises a base, a swing support, a first driving component, a first guide wheel, a sliding base, a second driving component, a first force measuring shaft pin and a first encoder, the swing support is connected with the base, the sliding base slides along the swing support, and the first guide wheel is installed on the sliding base. The A frame is connected with a ship body and provided with a motion reference unit; the oscillation stopping device comprises a second guide wheel, a second force measuring shaft pin and a second encoder and is installed on the A frame. The load device is provided with an inertial measurement unit. Through the controller, based on intelligent switching of tension control and wave compensation modes, the first driving part achieves passive compensation, the second driving part adjusts the tension of the umbilical cable according to the heaving motion, and safe and efficient operation of equipment is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of marine engineering, and in particular to an underwater robot retracting and deploying device and a retracting and deploying wave compensation method. Background Art

[0002] With the continuous advancement of marine technology, underwater robot technology has been widely used in many fields such as marine resource exploration, trenching and cable laying, and underwater engineering. However, when operating at sea, ships are often affected by waves and cause turbulence, which may pose a serious threat to the release and recovery process of underwater robots.

[0003] In actual operation, the swaying and pitching of the offshore vessel, as well as the inertia and resistance of the equipment in the water, will inevitably cause the umbilical cable to be pulled during the lowering and recovery process. However, the application effect of passive compensation technology is not ideal. The hydraulic cylinder used in this technology has a slow response speed and cannot quickly adapt to the needs of wave tracking. In addition, the monitoring performance of the hydraulic cylinder is poor, making it difficult to effectively monitor the movement speed.

[0004] The existing underwater robot heave compensation devices mainly include active, passive and active and passive combination. Among them, the passive heave compensation device has a simple structure but low precision and low compensation efficiency, and is difficult to adapt to complex sea conditions. The active heave compensation device has the advantages of high precision and high compensation efficiency, but it is expensive and has a complex structure. Summary of the invention

[0005] The invention provides an underwater robot retracting and releasing device and a retracting and releasing wave compensation method, which aims to solve the pulling problem of the umbilical cable of the underwater robot during the retracting and releasing process.

[0006] To achieve the above-mentioned object, the first aspect of the present invention provides an underwater robot retracting and launching device, the device comprising a cable storage winch, a wave compensation component, an A-frame, a sway stopper, a load device, an umbilical cable and a controller, one end of the umbilical cable is connected to the cable storage winch, the other end is connected to the load device, and passes through the wave compensation component and the sway stopper in sequence, wherein:

[0007] The wave compensation component comprises a base, a swing bracket, a first driving component, a first guide wheel, a sliding base, a second driving component, a first force measuring shaft pin, and a first encoder. The base is installed on the hull, one end of the swing bracket is rotatably arranged with the base, the first driving component is rotatably arranged with the base, the output end of the first driving component is rotatably connected to the swing bracket, a sliding base is slidably arranged on the swing bracket, the first guide wheel is installed on the sliding base, the second driving component is fixed on the swing bracket, and the output end thereof is connected to the sliding base; the first force measuring shaft pin and the first encoder are installed on the first guide wheel;

[0008] One end of the A frame is rotatably arranged with the hull, a third driving component is arranged on the hull, an output end of the third driving component is movably connected to the A frame, and a motion reference unit is installed on the A frame;

[0009] The anti-oscillation device comprises a frame, a second guide wheel, a second force-measuring shaft pin and a second encoder, wherein the frame is fixedly mounted on the A frame, the second guide wheel is rotatably mounted on the frame, and the second force-measuring shaft pin and the second encoder are mounted on the second guide wheel;

[0010] The load device is provided with an inertial measurement unit;

[0011] Wherein, the first force measuring pin, the second force measuring pin, the first encoder, the second encoder, the motion reference unit and the inertial measurement unit are connected to the controller.

[0012] Furthermore, the load equipment is an ROV, a trencher or an emplacement plow.

[0013] Furthermore, the wave compensation component also includes a fixed bracket, one end of which is rotatably connected to the base, and the other end of which is connected to the swing bracket.

[0014] Furthermore, the device also includes a traveling car, which is located between the load device and the stabilizer, and the umbilical cable passes through the wave compensation component, the stabilizer and the traveling car in sequence.

[0015] Furthermore, the first driving component is a hydraulic cylinder.

[0016] Furthermore, the second driving component is an electric cylinder.

[0017] To achieve the above-mentioned purpose, the second aspect of the present invention provides a wave compensation method for retracting and deploying an underwater robot, the method is implemented by the device, and the method comprises the following steps:

[0018] Calculating the umbilical cable tension according to the measurements of the first force measuring pin and the second force measuring pin;

[0019] Determine the amplitude of the tension curve of the umbilical cable tension. If the amplitude is less than the set threshold, enter the standby state and turn off the passive heave compensation and active heave compensation; otherwise, continue to determine the frequency of the tension curve;

[0020] If the frequency is less than the set threshold, passive heave compensation is turned on and active heave compensation is turned off; otherwise, both passive heave compensation and active heave compensation are turned on.

[0021] Further, passive heave compensation comprises the following steps:

[0022] Determine whether passive wave compensation is enabled. If enabled, proceed to the next step.

[0023] Determine the tension of the umbilical cable, if the tension of the umbilical cable is greater than a set tension threshold, release the cable through the first driving component to reduce the tension; if the tension of the umbilical cable is less than the set tension threshold, tighten the cable through the first driving component to increase the tension;

[0024] Repeat the above steps until the process is completed.

[0025] Further, active heave compensation comprises the following steps:

[0026] Determine whether active wave compensation is enabled. If enabled, proceed to the next step.

[0027] The relative heave between the hull and the load device is calculated according to the motion reference unit and the inertial measurement unit to determine the amplitude; if the amplitude is less than the set amplitude threshold, adjustments are made according to the heave of the hull: if the heave of the hull is rising, the second driving component is started to drive the sliding base to tighten the umbilical cable to increase the tension; if the heave of the hull is falling, the second driving component is started to drive the sliding base to release the umbilical cable to reduce the tension;

[0028] Repeat the above steps until the process is completed.

[0029] Furthermore, the method also includes monitoring the rate of change of the umbilical cable tension in real time by the controller during the switching process between active wave compensation and passive wave compensation, and if the rate of change of the tension exceeds a preset threshold, passive wave compensation is preferentially turned on.

[0030] Beneficial effects of the present invention:

[0031] Compared with the prior art, the underwater robot retracting and launching device and the retracting and launching wave compensation method provided by the present invention solve the problems of low precision and slow response of traditional devices by integrating active and passive wave compensation technologies. This solution monitors the posture changes of the hull and the load equipment in real time through the motion reference unit (MRU) installed on the hull and the inertial measurement unit (IMU) on the load equipment to accurately control the action of the compensation device. The device adopts an intelligent switching mechanism between tension control and wave compensation mode. In passive wave compensation, the tension is adjusted by the first driving component; in active wave compensation, the sliding base is driven by the second driving component to dynamically retract and launch the umbilical cable according to the heave movement, thereby ensuring that the umbilical cable maintains tension balance in complex sea conditions and avoiding damage to the equipment caused by excessive tension. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0033] Figure 1 The present invention is a schematic diagram of the overall structure of an underwater robot retracting and deploying device disclosed in an embodiment of the present invention.

[0034] Figure 2 It is a schematic diagram of the overall structure of an anti-oscillation device disclosed in an embodiment of the present invention.

[0035] Figure 3 It is a schematic diagram of the overall structure of a heave compensation component disclosed in an embodiment of the present invention.

[0036] Figure 4 The present invention is a schematic diagram of passive compensation of an underwater robot retracting and launching device disclosed in an embodiment of the present invention.

[0037] Figure 5 The present invention is a schematic diagram of an active compensation device for an underwater robot disclosed in an embodiment of the present invention.

[0038] Figure 6 The present invention discloses a flow chart of a method for compensating for the retraction and deployment of an underwater robot.

[0039] Figure 7 The present invention discloses a flow chart of a passive compensation control method for an underwater robot retracting and launching device.

[0040] Figure 8 The present invention discloses a flow chart of an active compensation control method for an underwater robot retracting and launching device.

[0041] Figure numerals: 1. cable storage winch; 2. wave compensation component; 3. A frame; 4. stabilizer; 5. load equipment; 6. umbilical cable; 7. traveling car; 8. hull; 20. base; 21. swing bracket; 22. first drive component; 23. first guide wheel; 24. sliding base; 25. second drive component; 26. first force measuring pin; 27. first encoder; 28. fixed bracket; 30. third drive component; 31. motion reference unit; 40. frame; 41. second guide wheel; 42. second force measuring pin; 43. second encoder; 50. inertial measurement unit. DETAILED DESCRIPTION

[0042] The specific implementation of the present invention is described in detail below with reference to the accompanying drawings. The implementation of the present invention is only an illustrative example and does not limit the protection scope of the present invention.

[0043] like Figure 1 As shown, the present invention provides an underwater robot retracting and launching device, including a cable storage winch 1, a wave compensation component 2, an A frame 3, a stabilizer 4, a load device 5, an umbilical cable 6 and a controller.

[0044] The cable storage winch 1 is used for retracting and releasing the umbilical cable 6. One end of the umbilical cable 6 is connected to the cable storage winch 1, and the other end is connected to the load device 5, and passes through the wave compensation component 2 and the stabilizer 4 in sequence. The umbilical cable 6 is connected to the underwater robot (load device 5) and is responsible for power, signal and mechanical transmission.

[0045] The wave compensation component 2 is responsible for providing wave heave compensation for the umbilical cable 6, and can switch between active compensation and passive compensation modes according to the operating conditions. The A-frame 3 is used in the deployment and recovery process of the underwater robot to smoothly transfer the load equipment 5 from the deck to the water surface, and ensure safe retrieval into the ship during the recovery phase. The stabilizer 4 is installed on the A-frame 3 to reduce the vibration of the load equipment 5 during the deployment and recovery process. The load equipment 5 includes but is not limited to underwater robots such as ROV, trenchers, and burying plows, equipped with an inertial measurement unit 50 (IMU) to monitor the position and posture of the underwater robot. The controller receives signals from each force measuring pin, encoder, motion reference unit 31 and inertial measurement unit 50 to control the working state of the wave compensation component 2.

[0046] like Figure 3As shown, the wave compensation component 2 is installed on the hull 8, including a base 20, a swing bracket 21, a sliding base, a first driving component 22 (such as a hydraulic cylinder), a second driving component 25 (such as an electric cylinder), a first guide wheel 23, a first force measuring shaft pin 26, a first encoder 27, an accumulator and a controller. The base 20 is fixedly installed on the hull 8, and is used to support and stabilize the entire wave compensation component 2. One end of the swing bracket 21 is rotatably connected to the base 20 through a rotating shaft, and the other end of the swing bracket 21 is connected to the first driving component 22 (hydraulic cylinder), and can swing within a certain range according to the action of the hydraulic cylinder. The sliding base 24 is installed on the swing bracket 21 and can move along the slide rail of the swing bracket 21. Its sliding movement is controlled by the second driving component 25 (electric cylinder). The first guide wheel 23 is mounted on the sliding base 24 and is used to guide the umbilical cable 6. The first force measuring pin 26 and the first encoder 27 are mounted on the first guide wheel 23. In this embodiment, the first force measuring pin 26 is mounted on the rotating shaft of the first guide wheel 23, and the first encoder 27 is mounted on the edge of the wheel body of the first guide wheel 23. The first force measuring pin 26 is used to measure the tension of the umbilical cable 6, and the first encoder 27 is used to measure the cable length and speed of the umbilical cable 6. The first driving component 22 (hydraulic cylinder) is responsible for realizing passive wave compensation, and the driving energy is provided to the first driving component 22 through the connected accumulator. The second driving component 25 (electric cylinder) is responsible for realizing active wave compensation, and the length and tension of the umbilical cable 6 are adjusted by driving the sliding base 24 to slide along the swing bracket 21.

[0047] like Figure 1 As shown, the A-frame 3 is a key deployment and recovery structure on the hull 8, one end of which is connected to the hull 8 through a rotating shaft, and the other end is controlled by a third driving component 30 (hydraulic cylinder or motor). The A-frame 3 is equipped with a motion reference unit 31 (MRU), which is used to measure the position and posture of the hull 8, mainly the heave displacement.

[0048] like Figure 2 As shown, the stabilizer 4 is fixedly mounted on the A frame 3, and includes a frame 40, a second guide wheel 41, a second force measuring pin 42 and a second encoder 43. The frame 40 is fixed on the A frame 3, and is used to provide mechanical support for the stabilizer 4. The second guide wheel 41 is rotatably arranged with the frame 40, and is used to further guide the umbilical cable 6, and reduce the vibration of the load device 5 during the deployment and recovery stages. Similarly, the second force measuring pin 42 is mounted on the rotating shaft of the second guide wheel 41, and the second encoder 43 is mounted on the wheel edge of the second guide wheel 41 or the frame 40. The second force measuring pin 42 and the second encoder 43 are used to measure the tension of the umbilical cable 6 and the cable length and speed.

[0049] The load device 5 is an underwater robot, including but not limited to ROV, trencher, burying plow, etc. The load device 5 is equipped with an inertial measurement unit 50 (IMU) to monitor the position information of the underwater robot in real time and feed the data back to the controller for adjusting the action of the wave compensation component 2.

[0050] In some embodiments, the wave compensation component 2 further includes a fixed bracket 28, one end of the fixed bracket 28 is rotatably connected to the base 20, and the other end is connected to the swing bracket 21; the fixed bracket 28 is mainly used to improve the structural strength of the equipment.

[0051] In some embodiments, the entire device further includes a traveling carriage 7, which is located between the load device 5 and the stabilizer 4, and the umbilical cable 6 sequentially passes through the wave compensation component 2, the stabilizer 4 and the traveling carriage 7. The traveling carriage 7 (Cursor) is mainly used to lift the heavy underwater robot and reduce the tension of the umbilical cable 6 after it is out of water. For small and medium-sized underwater robots, this component is not necessary.

[0052] like Figure 4-Figure 8 To achieve the above purpose, the present invention also provides a wave compensation method for retracting and deploying an underwater robot. The method is implemented by the above device, and the specific steps of the method are as follows:

[0053] S1: Measure the umbilical cable tension T=(Ta+Tb) / 2 according to the force measuring pin, wherein Ta is the tension value measured by the first force measuring pin 26, and Tb is the tension value measured by the second force measuring pin 42;

[0054] S2: Make a judgment based on the amplitude A of the tension curve T(t). If the amplitude A is less than the set threshold ALim, then go to step S41, otherwise go to step S3;

[0055] S3: Make a judgment based on the frequency f of the tension curve T(t). If the frequency f is less than the set threshold fLim, then go to step S42; otherwise, go to step S43;

[0056] S41: The heave compensation component 2 will enter the standby state, and both the passive heave compensation and the active heave compensation will be turned off;

[0057] S42: The heave compensation component 2 will enter the passive compensation state, the passive heave compensation is turned on, and the active heave compensation is turned off;

[0058] S43: The heave compensation component 2 will enter a semi-active compensation state, with both passive heave compensation and active heave compensation being turned on.

[0059] The passive heave compensation of the present invention adopts the first driving component 22, see Figure 4 and Figure 7 , the specific steps are as follows:

[0060] S51: Determine whether passive wave compensation is enabled. If it is enabled, proceed to step S61; otherwise, end the process.

[0061] S61: Judge according to the tension T of the umbilical cable 6. If the tension is too large, T > TLim, then proceed to step S811; otherwise, proceed to step S71, where TLim is the set threshold.

[0062] S71: Judge according to the tension T of the umbilical cable 6. If the tension is too small, T < TLim, then proceed to step S812; otherwise, proceed to step S91.

[0063] S811: The increase in tension causes the first driving component 22 (oil cylinder) to compress, storing energy in the accumulator, thereby releasing part of the umbilical cable 6, reducing the tension, and driving the load device 5 (underwater robot) to descend.

[0064] S812: The increase in tension causes the first driving component 22 (oil cylinder) to extend, releasing the energy in the accumulator, thereby tightening part of the umbilical cable 6, increasing the tension, and driving the load device 5 (underwater robot) to ascend.

[0065] S91: Judge whether the process ends. If it does not end, return to step S61.

[0066] The active wave compensation described in the present invention adopts a control method of collecting the heave motion of the hull to drive the second driving component 25, as shown in Figure 5 and Figure 8 , and the specific steps are as follows:

[0067] S52: Determine whether the system enables active wave compensation. If it is enabled, proceed to step S62; otherwise, end the process.

[0068] S62: Calculate the relative heave ΔX of the hull 8 and the underwater robot according to the motion reference unit 31 (MRU) and the inertial measurement unit 50 (IMU). Judge through the relative heave curve ΔX(t). If the amplitude Ax is less than the set threshold AxLim, then proceed to step S72; otherwise, proceed to step S92.

[0069] S72: Judge according to the heave X of the hull 8. If the heave X is ascending and cable retraction is required, then proceed to step 821; if the heave X is descending and cable release is required, proceed to step S822.

[0070] S821: Drive the second driving component 25 (electric cylinder) to contract, driving the first guide wheel 23 to move upward, thereby tightening part of the umbilical cable 6, increasing the tension, and driving the load device 5 (underwater robot) to ascend.

[0071] S822: driving the second driving component 25 (electric cylinder) to extend, driving the first guide wheel 23 to move downward, thereby releasing part of the umbilical cable 6, reducing tension, and driving the load device 5 (underwater robot) to descend;

[0072] S92: Determine whether the process is finished. If not, return to step S62.

[0073] In this embodiment, by introducing a real-time monitoring mechanism of the umbilical cable tension change rate during the switching process between active heave compensation and passive heave compensation, the safety and intelligence of the device are further improved. When it is detected that the umbilical cable tension change rate exceeds a preset threshold, passive heave compensation is started first to quickly respond to the sudden change in tension and avoid umbilical cable breakage or load equipment damage due to instantaneous overload.

[0074] By integrating active and passive wave compensation technologies, the present invention can quickly respond to the wave rise and fall of the hull, ensure the dynamic balance of the tension of the umbilical cable 6, and avoid the problem of equipment damage caused by slow response speed or low control accuracy in the prior art. At the same time, the device has a reasonable structural design, good versatility and economy, and can be widely used in underwater robot deployment and recovery operations under complex sea conditions.

[0075] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0076] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0077] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An underwater robot retracting and deploying device, characterized in that: The device comprises a cable storage winch, a wave compensation component, an A-frame, a stabilizer, a load device, an umbilical cable and a controller, one end of the umbilical cable is connected to the cable storage winch, the other end is connected to the load device, and passes through the wave compensation component and the stabilizer in sequence, wherein: The wave compensation component comprises a base, a swing bracket, a first driving component, a first guide wheel, a sliding base, a second driving component, a first force measuring shaft pin, and a first encoder. The base is installed on the hull, one end of the swing bracket is rotatably arranged with the base, the first driving component is rotatably arranged with the base, the output end of the first driving component is rotatably connected to the swing bracket, a sliding base is slidably arranged on the swing bracket, the first guide wheel is installed on the sliding base, the second driving component is fixed on the swing bracket, and the output end thereof is connected to the sliding base; the first force measuring shaft pin and the first encoder are installed on the first guide wheel; One end of the A frame is rotatably arranged with the hull, a third driving component is arranged on the hull, an output end of the third driving component is movably connected to the A frame, and a motion reference unit is installed on the A frame; The anti-oscillation device comprises a frame, a second guide wheel, a second force-measuring shaft pin and a second encoder, wherein the frame is fixedly mounted on the A frame, the second guide wheel is rotatably mounted on the frame, and the second force-measuring shaft pin and the second encoder are mounted on the second guide wheel; The load device is provided with an inertial measurement unit; Wherein, the first force measuring pin, the second force measuring pin, the first encoder, the second encoder, the motion reference unit and the inertial measurement unit are connected to the controller.

2. The underwater robot retracting and deploying device according to claim 1, characterized in that: The load equipment is an ROV, a trencher or an emplacement plow.

3. The underwater robot retracting and deploying device according to claim 1, characterized in that: The wave compensation component also includes a fixed bracket, one end of which is rotatably connected to the base, and the other end of which is connected to the swing bracket.

4. The underwater robot retracting and deploying device according to claim 1, characterized in that: The device further comprises a traveling carriage, wherein the traveling carriage is located between the load device and the oscillator, and the umbilical cable passes through the heave compensation component, the oscillator and the traveling carriage in sequence.

5. The underwater robot retracting and deploying device according to claim 1, characterized in that: The first driving component is a hydraulic cylinder.

6. The underwater robot retracting and deploying device according to claim 1, characterized in that: The second driving component is an electric cylinder.

7. A wave compensation method for deploying and retracting an underwater robot, characterized in that: The method is implemented by the device according to any one of claims 1 to 6, and the method comprises the following steps: Calculating the umbilical cable tension according to the measurements of the first force measuring pin and the second force measuring pin; Determine the amplitude of the tension curve of the umbilical cable tension. If the amplitude is less than the set threshold, enter the standby state and turn off the passive heave compensation and active heave compensation; otherwise, continue to determine the frequency of the tension curve; If the frequency is less than the set threshold, passive heave compensation is turned on and active heave compensation is turned off; otherwise, both passive heave compensation and active heave compensation are turned on.

8. The underwater robot retracting and deploying wave compensation method according to claim 7, characterized in that: Passive heave compensation includes the following steps: Determine whether passive wave compensation is enabled. If enabled, proceed to the next step. Determine the tension of the umbilical cable, if the tension of the umbilical cable is greater than a set tension threshold, release the cable through the first driving component to reduce the tension; if the tension of the umbilical cable is less than the set tension threshold, tighten the cable through the first driving component to increase the tension; Repeat the above steps until the process is completed.

9. The underwater robot retracting and deploying wave compensation method according to claim 7, characterized in that: Active heave compensation includes the following steps: Determine whether active wave compensation is enabled. If enabled, proceed to the next step. The relative heave between the hull and the load device is calculated according to the motion reference unit and the inertial measurement unit to determine the amplitude; if the amplitude is less than the set amplitude threshold, adjustments are made according to the heave of the hull: if the heave of the hull is rising, the second driving component is started to drive the sliding base to tighten the umbilical cable to increase the tension; if the heave of the hull is falling, the second driving component is started to drive the sliding base to release the umbilical cable to reduce the tension; Repeat the above steps until the process is completed.

10. The underwater robot retracting and deploying wave compensation method according to claim 7, characterized in that: The method also includes monitoring the rate of change of the umbilical cable tension in real time by the controller during the switching process between active heave compensation and passive heave compensation, and if the rate of change of the tension exceeds a preset threshold, giving priority to starting the passive heave compensation.

Images